Chapter 907, EVIDENCE — OPINIONS AND EXPERT TESTIMONY

907.01 Opinion testimony by lay witnesses. If the witness is not testifying as an expert, the witness’s testimony in the form of opinions or inferences is limited to those opinions or inferences which are all of the following: (1) Rationally based on the perception of the witness…

907.02 Testimony by experts. (1) If scientific, technical, or other specialized knowledge will assist the trier of fact to understand the evidence or to determine a fact in issue, a witness qualified as an expert by knowledge, skill, experience, training, or education, may testif…

907.03 Bases of opinion testimony by experts. The facts or data in the particular case upon which an expert bases an opinion or inference may be those perceived by or made known to the expert at or before the hearing. If of a type reasonably relied upon by experts in the particul…

907.04 Opinion on ultimate issue. Testimony in the form of an opinion or inference otherwise admissible is not objectionable because it embraces an ultimate issue to be decided by the trier of fact. History: Sup. Ct. Order, 59 Wis. 2d R1, R211 (1973).

907.05 Disclosure of facts or data underlying expert opinion. The expert may testify in terms of opinion or inference and give the reasons therefor without prior disclosure of the underlying facts or data, unless the judge requires otherwise. The expert may in any event be requir…

907.06 Court appointed experts. (1) APPOINTMENT. The judge may on the judge’s own motion or on the motion of any party enter an order to show cause why expert witnesses should not be appointed, and may request the parties to submit nominations. The judge may appoint any expert wi…

907.07 Reading of report by expert. An expert witness may at the trial read in evidence any report which the witness made or joined in making except matter therein which would not be admissible if offered as oral testimony by the witness. Before its use, a copy of the report shal…